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«TED STATES DEPARTMENT OF AGRICULTURE 




No. 1123 J 



SL&QmfL. 




s^*%^ru 



Washington, D. C. 



November 6, 1922 



PROPORTIONING THE INGREDIENTS FOR ICE CREAM AND 

OTHER FROZEN PRODUCTS BY THE 

BALANCE METHOD. 1 

/ / 
By O. E; Williams, Dairy Manufacturing Specialist, Dairy Division, Bureau of 
xv Animal Industry. 



CONTENTS. 



The balance method 1 

Five basic conditions 2 

How the ingredients are proportioned 2 

Examples 1 to 5 .- - 2 

Rough estimates for proportioning ingredients 10 

Adjustment of composition 11 



THE BALANCE METHOD. 

One of the most satisfactory methods that can be used for pro- 
portioning the ingredients in making large ice-cream mixes is " the 
balance metjiod, " a term originated in connection with the work 
here reported. It is a method that can be easily understood, is 
applicable to all combinations of ingredients, and reduces to a mini- 
mum the chances of error in the calculations. Furthermore, it 
furnishes an itemized record of the ingredients used for each mix. 
In the examples given, the calculations include decimal fractions, 
but for all practical trade purposes the nearest whole number is 
sufficiently accurate, especially when they represent constituents 
amounting to 100 pounds or more. The proportions obtained by this 
method are based on five conditions: 

1. The amount (pounds) of mix that will be necessary to pro- 
duce the number of gallons of ice cream desired. 

2. The composition (standard) of ice cream desired. 

3. The amount of solid constituents necessary for the mix. 

4. The quantity and physical condition of the ingredients on 
hand. 

5. The composition of the ingredients to be used. 

1 This Bulletin is a technical discussion of a method of calculating mixes of ice cream and other frozen 
products. It should not be construed as recommending the formulas presented, for not all of them would be 
legal in all States. Each user should give consideration to the legal standards concerned. 

Part of the material in this bulletin was first published in the Journal of Dairy Science, Vol. Ill, No. 6, 
November, 1920. 

8115°— 22— Bull. 1123 






H 



2 mi. i i: UN 1123, r. S. DEPARTMENT OF AGRICULTURE. 

FIVE HASH' CONDITIONS. 

Condition I. -To get the total Dumber of pounds in the mix, 
multiply the desired number of gallons of ice cream by the number of 
pounds expected in one gallon of the finished product. For instance, 

m the first example .") pounds is the desired weight of one gallon of 
ice cream, hence: 

350 X 5= 1,750 pounds of mix. 

( bndition £.— The approximate composition of the ice cream desired 
in the first example is 14.5 per cent fat, 14 per cent sugar, and 6.5 per 
rent milk solids not fat. 

( audition J. --To find the amount of solid constituents necessary, 
multiply the pounds of mix by the percentage of fat, sugar, and milk 
solids not fat as in the first example: 

1,750X0.145 = 253.75 pounds of fat. 
1 ,750 X 0. 14 = 245.0 pounds of sugar. 
1,750X0.065= 113.75 pounds of milk solids not fat. 

Conditions 4 and 5. — The quantity on hand and composition of the 
ingredients are as follows: 





Quantity on hand. 


Composition. 


Ingredients. 


Fat. 


Sugar. 


Milk 

solids not 

fat. 


Cream 


150 pounds 


Per cent. 
28 
43 


Per cent. 


Per cent. 
6.4 


Cream. . 


Plenty 




5.3 


Skim milk 


do 




9 


Condensed milk 


430 pounds 


10 


42 


22 









After these basic conditions are determined, write the pounds of 
mix, the percentage of constituents desired, and the pounds of each 
constituent in table form and list the ingredients to be considered for 
the mix as shown in Table 1 . 

HOW THE INGREDIENTS ARE PROPORTIONED. 

Five examples of this method of proportioning the ingredients are 
explained as follows: 

EXAMPLE 1. 

Give the proportions for 350 gallons of ice cream testing approxi- 
mately 14.5 per cent fat, 14 per cent sugar, and 6.5 per cent milk 
solids not fat. The weight of the ice cream desired is 5 pounds per 
gallon. 

Stock on hand: Sugar; 150 pounds of 28 per cent cream; 520 
pounds of 43 per cent cream; and skim milk. 



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LIBRARY OP CONGfcg* 

NOV 9-1922 

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PROPORTIONING THE INGREDIENTS FOR ICE CREAM. 
Table 1. — Illustration of Example 1 . 



Total pounds 
desired 

(5X350=1,750). 



Pounds. 

245.0 
150.0 
492.5 
862.5 



1, 750. 



Ingredients and composition. 



Sugar 

Cream, 28 per cent . . . 
Cream, 43 per cent . . . 
Skim milk, 9 per cent . 



Constituents furnished. 



Fats 

(14.5 per 

cent, 253.75 

pounds). 



Pounds. 



42.00 
211. 77 



253. 77 



Sugar 

(14 per 

cent, 245 

pounds). 



Pounds. 
245 



245 



Milk 

solids not 

fat (6.5 per 

cent, 113.7 

pounds). 



Pounds. 



ilO.O 

126.1 

77.6 



2 113.7 



i The amount of milk solids not fat in the cream is determined by multiplying the difference between the 
amount of cream used and the amount of fat it contains by 0.093 (the amount of milk solids not fat in the 
milk serum). 

2 The amount of milk solids not fat in the mix is normal, i. e., the amount resulting from the use of sugar, 
cream, and whole or skim milk; consequently the figures given in this example are simply to explain a 
procedure that is applicable to the use of other milk products, such as butter, condensed milkj etc., and 
are not intended to satisfy the particular requirement of 6.5 per cent, which may vary according to the 
milk-solids-not-fat content of the skim milk. 



METHOD OF CALCULATING THE INGREDIENTS. 

The calculations necessary in determining the proportions of the 
ingredients to be used are as follows (consider the ingredients as 
they are listed) : • 

Sugar.— The amount of sugar is the same as the amount calcu- 
lated for the mix, since there is no cane sugar in the other ingredients. 

Cream {28 per cent). — The 150 pounds of 28 per cent cream does 
not contain more fat than is needed; hence the entire amount can 
be used. 

Cream (43 per cent). — The amount of 43 per cent cream can be 
determined by subtracting the amount of fat added by the 150 
pounds of 28 per cent cream from the total amount required and 
dividing the remainder by 0.43, thus: 

253.77-42-211.77. 

211.77^0.43=492.5 pounds of 43 per cent cream. 

Skim milk. — From this ingredient will come the remainder of the 
constituents (milk solids not fat) of the mix. The amount required 
will be the difference between the amount of ingredients already 
used, and the total (1,750) pounds required. For instance, 1,750 — 
(245 + 150 + 492.5) =862.5 pounds of skim milk. 

EXAMPLE 2. 

Give the proportions for 500 gallons of ice cream testing approxi- 
mately 14.5 per cent fat, 13 per cent sugar, 9 per cent milk solids 
not fat, and 0.5 per cent gelatin. The weight of the ice cream de- 
sired is 5 pounds per gallon. 

Stock on hand: Sugar; gelatin; 342 pounds of 30.5 per cent cream; 
1,608 pounds of 38 per cent cream; 720 pounds of sweetened con- 
densed milk containing 8.2 per cent fat, 42 per cent sugar, and 21 
per cent milk solids not fat ; and skim-milk powder: 



4 Bri.LKTlN L123, CJ. S. DEPAB I'MK.NT OV M\ R [( U' 1 ;vv UK. 

Tabi b 2. — Illustration of Example J. 



Total 
pounds 
desired, 
5X500 

2,500. 



rounds. 

23. 

12. 
342. 
524. 
720. 



23. 
855. 



;>ixi. o 



ingredients and composition. 



Granulated sugar 

Gelatin (powdered) 

Cream, 30.5 per cent 

Cream , 38 per cent 

Condensed milk 8.2 per cent fat, 42 per 
cent sugar, 21 per cent milk solids not 
fat 

Skim-milk powder 

Water 



Constituents furnished; 



Pal (14.5 Sugar (13 

per cent, per cent, 

362.5 325 

pounds). pounds). 



Pounds. 



104.3 
199. 



59. 



362. 3 



Pounds. 
23.0 



302. 



325. 



Milk 
solids not 
fat (9 per 

cent, 225 
pounds). 



Pounds. 



22.0 
30. 



151.0 
22.0 



225.0 



Gelatin 
(0.5 per 
cent. 12.5 
pounds). 



Pounds. 
" "12.5 



12.5 



METHOD OF CALCULATING THE INGREDIENTS. 

The calculations necessary in determining the proportions are as 
follows (consider the ingredients as they are listed) : 

Granulated sugar. — The amount of granulated sugar can not be 
determined until the sweetened condensed milk is proportioned. 

Gelatin (powder). — The amount of gelatin is the same as that cal- 
culated for the mix. 

Cream. — The 342 pounds of 30.5 per cent cream does not contain 
more than a small proportion of the fat required; hence the entire 
amount can be used. 

The amount of 38 per cent cream required can not be propor- 
tioned until after the condensed milk is proportioned, since the 
latter contains 8.2 per cent fat. 

Sweetened condensed milk. — The amount of sweetened condensed 
milk that can be used is limited by the amount of sugar and milk 
solids not fat it adds to the mix. The 720 pounds of sweetened con- 
densed milk will add only 302 pounds of sugar and 151 pounds of 
milk solids not fat; hence the entire amount can be used. 

Granulated sugar. — With the condensed milk proportioned, the 
amount of granulated sugar necessary can be determined by sub- 
tracting the amount added in the condensed milk from the total 
amount required, thus: 

325 — 302 = 23 pounds of granulated sugar. 

Cream (38 per cent). — Now that the condensed milk is propor- 
tioned, the amount of 38 per cent cream may also be determined. 
The amount is obtained by subtracting the sum of the fat contained 
in the 342 pounds of 30.5 per cent cream and the 720 pounds of 8.2 
per cent condensed milk from the total amount required and dividing 
the remainder by 0.38, thus: 

362.5- (104.3 + 59.0) =199.2. 

199.2-5-0.38 = 524 pounds of 38 per cent cream. 

Skirn-railk powder. — From this ingredient must come the remainder 
of the milk solids not fat needed in the mix. This is determined 



PROPORTIONING THE INGREDIENTS EOR ICE CREAM. 



5 



by the difference between the sum of the milk solids not fat added 
by the cream 2 and condensed milk and the total amount required 
plus 5 per cent. 3 For instance: 

225- (22 + 30 + 151) =22. 
22+ (0.05X22) =23.1. 

Water. — The required amount of solid constituents having been 
provided, the amount of water needed will be the difference between 
the total amount of mix required and the sum of the ingredients 
used. 

The accuracy of the calculations can be ascertained by comparing 
the sum of the figures in each column with the stipulated amounts 
placed at the top of each column. 

When this is done, the ingredients are proportioned by careful 
weighing. The mix is then ready to be pasteurized and homo- 
genized. 

EXAMPLE 3. 

Give the proportions for 350 gallons of frozen product testing ap- 
proximately 9 per cent fat, 14 per cent sugar, 12 per cent milk solids 
not fat, and 0.5 per cent gelatin. The weight of the product de- 
sired is 5 pounds per gallon. 

Stock on hand: Sugar; gelatin; 150 pounds of 28 per cent cream, 
480 pounds of 34 per cent cream; skim milk; and 900 pounds of con- 
densed skim milk, unsweetened. 

Table 3. — Illustration of Example 3. 



Total 
pounds 
desired, 

1,750. 



Pounds. 
245.0 
87.5 
150.0 
340.0 
397.0 
530.0 



1.749.5 



Ingredients and composition. 



Cane sugar 

Gelatin solution, 10 per cent 

Cream, 28 per cent 

Cream, 34 per cent 

Skim milk, 9 per cent 

Condensed skim milk, 27 per cent. 



Constituents furnished. 



Fat (9 per 
cent, 157.6 
pounds). 



Pounds. 



42.0 
115.6 



157.6 



Sugar (14 

per cent,245 

pounds). 



Pounds. 
245 



245 



Milk solids 

not fat (12 

per cent ,210 

pounds) 



Pounds. 



10.0 

20.8 

35.8 

143.0 



209.6 



Gelatin 

(0.5 per 

cent, 8.75 

pounds). 



Pounds. 
8." 75 



8.75 



METHOD OF CALCULATING THE INGREDIENTS. 

The calculations necessary in determining the proportions are as 
follows (consider the ingredients as they are listed) : 

Sugar. — The amount of sugar is the same as the amount calculated 
for the mix, since there is no cane sugar in the other ingredients. 

Gelatin. — The amount of gelatin solution is determined by moving 
the decimal point one place to the right, since the solution is a 10 per 
cent mixture. 



2 The amount of milk solids not fat in the cream is determined by multiplying the difference between 
the amount of cream used and the amount of fat it contains by 0.093 (the amount of milk solids not fat in 
the milk serum). 

3 Skim-milk powder contains on an average 3.5 per cent moisture and 1.5 per cent fat; consequently an 
allowance of 5 per cent is made in balancing the milk solids not fat. 



6 BULLETIN U2a, l T . S. PKPAIMMKNT OV ACRICULTOKH. 

( Y< a ))).- The I 50 pounds of 28 per cent cream docs not contain more 
fat than is needed; hence the entire amount can be used. 

The amount of 34 per cent cream can he determined by subtracting 
the amount of fat added by (he L50 pounds of 28 per cent cream from 
the total amount required and dividing the remainder by 0.34, thus: 

157.5-42 = 115.5. 

115.5-^0.34 = 340 pounds of 34 per cent cream. 

Shim will' and, condensed shim milk. — From these two ingredients 
must come the balance of the constituents (milk solids not fat) of the 
mix. To find the proportions subtract the sum of the milk solids not 
fat in the cream from the total amount required and divide by 927.5, 
the difference between the amount of ingredients already used and 
the total (1,750) pounds required. For instance: 

210-(10 + 20.8) = 179.2. 

(179.2 -- 927.5) X 100 = 19.3 per cent solids. 

This gives the per cent of solids not fat that the additional 927.5 
pounds of mix must contain. To find the proportion of skim milk and 
condensed skim milk necessary, the " square method" is used. The 
calculations for the square method 4 are as follows: 



Skim milk 9 



Condensed milk 27 




7.7 



10.3 
18.0 



927.5-^-18=51.53 number of unit portions in total mix. 
51.53X7.7=396.78 pounds of skim milk in total mix. 
51.53X10.3=530.75 pounds of condensed skim milk in total mix. 

The accuracy of the calculation can be ascertained by comparing 
the sum of the figures in each column with the stipulated amounts 
placed at the top of each column. 

When this is done, the ingredients are proportioned by careful 
weighing. The mix is then ready to be pasteurized and homogenized. 

* The square method, sometimes called the Pearson method, may be used to find the proportion of milk 
and cream necessary in standardizing either the fat or the milk solids not fat in milk and cream. The 
purpose of the square is to separate the three principal factors in making the calculations, and to keep the 
deductions straight after the calculations have been made. For instance, in this particular problem, 
which is to find the proportion of skim milk and condensed skim milk necessary in making 927.5 pounds of 
skim milk containing 19.3 per cent milk solids not fat, the three principal factors are: First, the milk solids 
not fat content desired in the mixture; second, the milk solids not fat content of the skim milk; and third, 
the milk solids not fat content of the condensed skim milk. The first factor (19.3 per cent) is placed in the 
center of the square; and the other two factors (9 per cent and 27 per cent) are assigned to the corners on the 
left-hand side of the square. When this has been done, two calculations are made and placed as follows: 
(1) The difference between the upper left-hand figure (9) and the center figure (19.3), which is 10.3, is placed 
in the lower right-hand corner of the square, and indicates the number of pounds in a unit portion of the 
condensed skim milk required in the proposed mixture. Similarly the difference between the lower left- 
hand figure (27) and the center figure (19.3) which is 7.7, is placed in the upper right-hand corner of the 
square, and indicates the number of pounds in a unit portion of the skim milk required in the proposed 
mixture. Having ascertained the weight of one unit portion of each of these ingredients, any quantity 
of the desired mixture can easily be made by adding these two together to find the weight of one unit portion 
of the mixture desired, and then multiplying this by the number of unit portions in the total mix, as shown 
in the above example. The same procedure is used in standardizing the fat contents of milk and cream. 



PROPORTIONING THE INGREDIENTS FOR ICE CREAM. 7 

EXAMPLE 4. 

Give the proportions of the following ingredients necessary for 280 
gallons of a frozen product testing approximately 10 per cent fat, 8 
per cent sugar, and the equivalent of 6 per cent additional sugar in the 
form of maltose sugar sirup and corn sirup, 5 10 per cent milk solids not 
fat, and 0.5 per cent gelatin. The weight of the product desired is 4.5 
pounds per gallon. 

Stock on hand: Sugar; gelatin; maltose sugar sirup and corn sirup ; 
cream (221 pounds of 40 per cent, 80 pounds of 35 per cent, 82 pounds 
of 24 per cent, 78 pounds of 29.5 per cent, 64 pounds of 28 per cent, 
and 73 pounds of 19 per cent) ; sweetened condensed skim milk testing 
25 per cent milk solids not fat and 40 per cent sugar; and skim milk 
powder. 

Table 4. — Illustration of Example 4. 



Total pounds 
desired, 1,260. 



Pounds. 

63.0 
151.0 
80.0 
82.0 
78.0 
64.0 
73.0 
59.0 
252.5 

35.5 
322.0 



1, 260. 



Ingredients and composition. 



Granulated sugar (cane) 

Gelatin solution, 10 per cent 

Sirup, 80 per cent solids } 

Cream, 35 per cent 

Cream, 24 per cent 

Cream, 29.5 per cent 

Cream, 28 per cent 

Cream, 19 per cent 

Cream, 40 per cent 

Condensed skim milk, 25 per cent solids 

and 40 per cent sugar 

Skim-milk powder 

Water 



Constituents furnished. 



Fat (10 
per cent, 

126 
pounds). 



Pounds. 



28.0 
19.6 
23.0 
17.9 
13.8 
23.6 



125.9 



Sugar (8 
per cent, 

101 
pounds). 



Pounds. 



101.0 



101.0 



Milk solids 
not fat (10 

per cent, 
126 

pounds). 



Pounds. 



28.8 



63.0 
34.0 



125.8 



Gelatin 

(0.5 per 

cent, 6.3 

pounds). 



Pounds. 



6.3 



6.3 



1 The solids in the sirup weigh about 121 pounds. 

METHOD OF CALCULATING THE INGREDIENTS. 

The calculations necessary in determining the proportions are as 
follows (consider the ingredients as they are listed) : 

Granulated sugar. — The amount of granulated sugar can not be 
determined until the sweetened condensed milk is proportioned. 

Gelatin.— The amount of gelatin solution is determined, as in 
Example 3, by moving the decimal point one place to the right, 
since the solution contains 10 per cent of gelatin. 

Sirups. — The amount of sirup is determined by multiplying 1,260 
by the per cent desired, thus : 

1,260X0.12 =151.2 pounds of sirup. 

Cream. — Since all the different lots of cream are used except the 
lot testing 40 per cent, the sum of the first iive lots will add 102.3 
pounds of fat to the mix and the remainder is determined by dividing 



5 Maltose sugar sirup and corn sirup are only half as sweet as cane sugar; consequently to replace the 6 
per cent sugar it is necessary to use 12 per cent sirup. 



S lUl.l.K.riN L123, V. s. DEPARTMENT OK AGRICULTURE. 

the difference between 126 pounds and 102.3 pounds by the per 
ivnt of fat in the sixth lot. thus: 

L26.0 - (28 + L9.6 + 23 + 17.9+13.8) =23.6. 
23.6-^0.40 =59.0 pounds of 40 per cent cream. 

s> oeetenea condensed skim milk. — The amount of sweetened con- 
densed skim milk that can be used is limited by the amount of sugar 
it will add to the mix. Dividing the amount of sugar needed in the 
mix by the per cent of sugar in the sweetened condensed skim milk 
will give the amount of this milk that can be used, thus: 

101 -M).40 =252.5 pounds of sweetened condensed skim milk. 

Granulated sugar. — Since the required amount of sugar is added 
with the sweetened condensed milk, no granulated sugar is needed. 

Skirn-milk powder. — The amount of skim-milk powder is determined 
by subtracting the sum of the milk solids not fat added by the cream 6 
and the condensed milk from the total amount required and adding 
5 per cent, 7 thus : 

126 -(28.8 + 63) =34.2. 
34.2 +(34.2x0.05) =35.9. 

Water. — The required amount of solid constituents having been 
added, the amount of water needed will be the difference between 
the total amount of the mix required and the sum of the ingredients 
used. 

The accuracy of the calculations can be ascertained by comparing 
the sum of the figures in each column with the stipulated amounts 
placed at the top of each column. 

When this has been done the ingredients are proportioned by 
careful weighing. The mix is then ready to be pasteurized and 
homogenized. 

EXAMPLE 5. 

Give the proportions for 220 gallons of a frozen product testing 
approximately 10 per cent fat, 14 per cent sugar, 10 per cent milk 
solids not fat, and 0.5 per cent gelatin. The weight of the product 
desired is 4.5 pounds per gallon. 

Stock on hand: Sugar; gelatin; cream, 33 per cent; condensed 
milk testing 10 per cent fat and 22 per cent milk solids not fat; and 
whole milk testing 36 per cent fat. 

6 The amount of milk solids not fat in the cream is determined by multiplying the difference between 
the amount of cream used and the amount of fat it contains by 0.093. 

i Skim-milk powder contains, on an average, 3.5 per cent moisture and 1.5 per cent fat; consequently 
an allowance of 5 per cent is made in balancing the milk solids not fat. 



PROPORTIONING THE INGREDIENTS FOR ICE CREAM. 
Table 5. — Illustration of Example 5. 



9 



Total pounds 

desired, 
4.5X220=990. 



Pounds. 
138.5 
49.5 
185.0 
372.0 
245.0 



990.0 



Ingredients and composition. 



Sugar 

Gelatin, 10 per cent 

Cream, 33 per cent 

Whole milk, 3.6 per cent 

Condensed milk, 10 per cent fat, 22 per 
cent milk solids not fat 



Constituents furnished. 



Fat (10 

per cent, 

99 pounds). 



Pounds. 



61.0 
13.4 

24.5 



Sugar (14 
per cent, 

138.5 
pounds). 



Pounds. 
138.5 



Milk solids 

not fat (10 

per cent, 

99 pounds). 



Pounds. 



44.9 
53.9 



138.5 



98. 



Gelatin 

(0.5 per 

cent, 4.95 

pounds). 



Pounds. 



4.95 



4.95 



METHOD OF CALCULATING THE INGREDIENTS. 

The calculations necessary in determining the proportions are as 
follows (consider the ingredients as they are listed) : 

Sugar. — The amount of sugar is the same as the amount calculated 
for the mix, since there is no cane sugar in the other ingredients. 

Gelatin. — The amount of gelatin solution is determined by moving 
the decimal point one place to the right, since the solution is a 10 
per cent mixture. 

Cream (33 per cent) . — The amount of cream can not be proportioned 
until after the condensed milk is proportioned, since the latter con- 
tains 10 per cent fat. 

Whole milk {3.6 per cent). — Temporarily omitted for the same 
reason. 

Condensed milk. — The amount of condensed milk necessary in this 
case is determined by using a rough estimate (see p. 10). From this 
estimate it is found that 245 pounds is about the correct amount, thus: 

990- (138.5 + 49.5 + 245) -557. 

557 -(99 -24.5) =482.5. 

482.5X0.093=44.87. 

44.87 + 53.9 =98. 77 pounds of milk solids not fat. 

Cream (33 per cent) and whole milk (3.6 per cent). — From these two 
ingredients must come the remainder of the constituents (fat and solids 
not fat) of the mix. To find the amount of each, subtract the amount 
of fat added by the condensed milk from the total amount required 
and divide by 557, the difference between the amount of ingredients 
already used, and the total (990) pounds required, thus: 

99-24.5=74.5. 

74.5^557 X 100 =13.37 per cent in 557 pounds of milk. 

This gives the per cent of fat that the additional 557 pounds of mix 
must contain. To find the proportions of cream and whole milk that 



10 



BULLETIN 1123. T. S. DEPAKTMKXT OK ACIIUTLTIKF, 



are necessary, the square method 8 is used. The calculations for the 
square method arc as follows: 



33. 




9.77 



19. 63 

29. 40 total number of parts. 
557-^29.4=18.94. 

18.94X9.77=185 pounds of cream. 
18.94X19.63=372 pounds of whole milk. 

The accuracy of the calculations can be ascertained by comparing- 
the sum of the figures in each column with the stipulated amounts 
placed at the top of each column. 

When this has been done the ingredients are proportioned by 
careful weighing. The mix is then ready to be pasteurized and 
homogenized. 

ROUGH ESTIMATES FOR PROPORTIONING INGREDIENTS. 

Whenever a mix is made from an unlimited quantity of condensed 
whole milk the amount of condensed milk required is determined by 
first making a rough estimate. For instance, in example 5, it is not 
known what part of the total amount of milk solids not fat of the mix 
must come from the condensed milk, so that what is thought to be 
about the right amount is tried. In this case the figure taken to 
begin with was 220 pounds. This figure is taken because from expe- 
rience it is known that about 50 per cent of the milk solids not fat in 
the mix must come from the condensed milk. That quantity divided 
by 22 (the per cent of milk solids not fat in the condensed milk) 
shows that it will require about 220 pounds of the condensed milk. 
This amount would add 22 pounds of fat and 48.4 pounds of milk 
solids not fat to the milk. 

To tell whether or not this is right simply take the difference 
between the total amount of ingredients already calculated (that is, 
the pounds of sugar, gelatin, and condensed milk) and the total weight 
of the mix, and subtract the difference between the fat used in the 
condensed milk and the total amount required to find the amount of 
milk serum. Then multiply this figure by 0.093 to get approximately 
the amount of milk solids not fat that will come from the milk and 
cream and the sum of the two will indicate whether the proportions 
are correct, thus: 

990- (138.5 + 49.5 + 220) =582 pounds of milk and cream. 
582— (99 — 22) =505 pounds of milk serum. 
505 X 0.093 =47 pounds of milk solids not fat from serum. 
47 + 48.4 =95.4 pounds of milk solids not fat in mix. 



* See p. 6. 



PROPORTIONING THE INGREDIENTS FOR ICE CREAM. 11 

The total amount of milk solids not fat lacks about 3.35 pounds, 
so we increase the amount of condensed milk 25 pounds or to 245 
pounds, which gives practically the right amount as shown in the table. 

In case the quantity had been increased only 15 pounds the total 
amount of milk solids not fat would have been a trifle short of the 
amount desired. The amount of milk and cream is then calculated 
as heretofore explained. 

ADJUSTMENT OF COMPOSITION. 

After a mix has been made up it frequently happens that the per- 
centage of fat and milk solids not fat in the mix is found to be not as 
desired. In such cases the composition of the mix can be easily 
changed to approximate the percentage desired by the addition of 
water, cream, skim milk, condensed milk, or powdered milk, depend- 
ing on the nature of the adjustment to be made. Three common 
adjustments are briefly as follows : 

1. CORRECTING A MIX LOW IN FAT. 

(a) Size of original mix, 3,600 pounds. 

(b) Desired composition of original mix, fat 12 per cent, sugar 15 
per cent, gelatin 0.5 per cent. 

(c) Fat test of original mix, 11.5 per cent. 

(d) The difference is 0.5 per cent fat, indicating a shortage of 18 
pounds of fat in the mix. 

To correct the standardization with cream testing 34 per cent fat, 
together with sugar and gelatin, increase the size of the mix to 3,800 
pounds and calculate the amount of each constituent that is needed 
m the new mix. Then the difference between the amount of con- 
stituents necessary for the new mix and the amounts contained in the 
original mix furnishes a basis for adjusting the percentage of each 
constituent desired in the mix. For instance, the difference is 42 
pounds of fat, 30 pounds of sugar, and 1 pound of gelatin. 

3,800 X 0.12 =456 pounds of fat. 
3,600 X 0.115 =414 pounds of fat. 
456-414 =42 pounds of fat. 

The remaining constituents are calculated for the 200 pounds of 
additional mix with the original percentages, thus : 

200 X 0.15 =30 pounds sugar. 
200 X 0.005 =1 pound gelatin. 

The proportions of the additional ingredients necessary would, then, 
be as follows : 

123.5 pounds of 34 per cent cream. 
30 pounds of sugar. 

10 pounds of 10 per cent gelatin solution. 
36.5 pounds of skim milk. 

200 pounds total additional mix. 



\2 BULLETIN L123; r. S. DEPARTMENT OK A.GRiCTJLttTJttl!l. 

8. CORRECTING A MIX HIGH IN FAT. 

(a} Size of original mix, 3,600 pounds; 

(b) Desired composition of original mix, fat 12 per cent, sugar 14 
per 6ent, milk solids not fat S per cent, gelatin 0.5 per cent. 

(c) Fat test of original mix, 13 per cent. 

(ej) The difference is 1 per cent fat, indicating an excess of 36 
pounds of fat in the mix. 

To correct the standardization with plain condensed (3-1) skim 
milk, sugar, etc., increase the size of the mix to 3,900 pounds and 
calculate the amount of each constituent that is needed in the new 
mix. The basis for adjustment is the same as before, i. e., the 
difference between the amounts of the respective constituents neces- 
sary for the new mix and the amounts contained in the original mix. 
For instance, the difference is pounds of fat, 42 pounds sugar, 24 
pounds milk solids not fat, and i.5 pounds gelatin. 

3,900 X 0.12 =468 pounds of fat. 

3,600 X 0.13 =468 pounds of fat. 

300 X 0.14 =42 pounds of sugar. 

300 X 0.08 =24 pounds of milk solids not fat. 

300 X 0.005 =1.5 pounds of gelatin. 

The proportion of the additional ingredients necessary would, then, 
be: 

42 pounds sugar. 
92 pounds condensed skim milk. 
15 pounds 10 per cent gelatin solution. 
151 pounds water. 

300 pounds total additional mix. 

3. CORRECTING A MIX LOW IN BOTH FAT AND MILK SOLIDS NOT FAT. 

(a) Size of original mix, 3,600 pounds. 

(b) Desired composition of original mix: Fat 12 per cent, sugar 
13 per cent, milk solids not fat 10 per cent, gelatin 0.5 percent, total 
solids 35.5 per cent. 

(c) Fat test of original mix, 11 per cent. 

id) Total solid determination, 33.5 per cent. 

(e) The difference in fat is 1 per cent, or a shortage of 36 pounds 
of fat. 

(/) The difference in total solids is 2 per cent, but since the fat is 
1 per cent lower than desired, it indicates that the solids other than 
the fat are 1 per cent too low. 

(g) The amount of sugar added is then verified by checking the 
figures, and if these are found correct the difference of 1 per cent in 
total solids is attributed to a shortage of milk solids not fat. 

To correct the standardization with 34 per cent cream, skim-milk 
powder, sugar, etc., increase the size of the mix to 4,000 pounds and 
proceed as explained in cases 1 and 2. The difference will be 84 
pounds fat, 52 pounds sugar, 76 pounds milk solids not fat, and 2 
pounds gelatin. 



PROPORTIONING THE INGREDIENTS FOR ICE CREAM. 13 

4,000 X 0.12 =480 pounds of fat. 
3,600X0.11 =396 pounds of fat. 
480-396 =84 pounds of fat. 
400 X 0.13 =52 pounds of sugar. 
4,000 X 0.10 =400 pounds of milk solids not fat. 
• 3,600 X 0.09 =324 pounds of milk solids not fat. 
400 — 324 =76 pounds of milk solids not fat. 
400 X 0.005 =2 pounds of gelatin. 

The proportion of additional ingredients necessary would, then, be: 

247 pounds 34 per cent cream. 
52 pounds sugar. 
63 pounds skim-milk powder. 
20 pounds 10 per cent gelatin solution. 
18 pounds water. 

400 pounds total additional mix. 

The increase made in the size of the mixes is a matter that depends 
on the kind and composition of the ingredients used in making the 
adjustment and is usually kept as low as possible. 



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